Patent Document 1 discloses a rolling bearing assembly. A rolling roll of a rolling mill is supported by the rolling bearing assembly. The rolling bearing assembly includes a rolling bearing and a seal member. In the rolling bearing assembly of Patent Document 1, as shown in FIG. 7, a rolling bearing assembly 3 includes a rolling bearing 100 and first and second seal members 210, 220 that are mounted on this rolling bearing 100. A roll neck 4 of the rolling roll is supported rotatably about a horizontal axis via the rolling bearing 100.
The rolling bearing 100 includes a pair of first and second inner rings 101, 102 that are fitted on the roll neck 4, a plurality of first to third outer rings 103 to 105 that are fixed to a housing, and a plurality of tapered rollers 106 that are disposed in an annular space defined between the inner rings 101, 102 and the outer rings 103 to 105. The first and second inner rings 101, 102 are disposed so that one axial end portion of the first inner ring 101 and the other axial end portion of the second inner ring 102 abut against each other. Then, an annular groove 107 is provided on outer circumferences of portions of the first and second inner rings 101, 102 where the axial end portions thereof abut against each other. This annular groove 107 is formed by providing steps at the end portions of the first and second inner rings 101, 102.
A bearing seal 210 as the first seal member is mounted at each of axial sides of the rolling bearing 100. The bearing seal 210 has a lip portion 211 that is brought into sliding contact with an outer circumferential surface of each of the inner rings 101, 102. The bearing seal 210 prevents cooling water for cooling the rolling roll or a foreign matter from entering into the annular space 108 from a bearing external portion.
An inter-inner ring seal 220 as the second seal member is mounted in the annular groove 107 that is situated at an axially central portion of the rolling bearing 100.
The inter-inner ring seal 220 is made of an annular core metal portion 221 and an elastic portion 222 that is fixed to this core metal portion 221. The elastic portion 222 has a proximal end portion 223 that includes on an inner circumferential surface thereof a pair of fixing lips 223a that fit on a circumferential surface of the annular groove 107 that corresponds to the first inner ring 101, and an extending portion 224 that includes on an inner circumferential surface thereof a sliding contact lip 224a that is brought into contact with a circumferential surface of the annular groove 107 that corresponds to the second inner ring 102. The sliding contact lip 224a is designed to slide relative to the circumferential surface of the annular groove 107 that corresponds to the second inner ring 102 when the first ring 101 and the second inner ring 102 rotate relative to each other.
The inter-inner ring seal 220 prevents cooling water or rolling oil that passes between the abutting end portions of the first and second inner rings 101, 102 from an outer circumferential surface of the roll neck 4 to enter the annular groove 107 from entering the annular space 108 or grease inside the annular space 108 from leaking out of the annular space 108.